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4 years ago

Katie knew that 70 + 70 = 140. Explain how she can use this double to solve 70 + 89.

Mathematics

2 answers:

grigory [225]4 years ago

8 0

Just add 19 to 140.

White raven [17]4 years ago

6 0

She can use this double by first finding the different in between 70 and 89, which is 19. After finding that difference she should add 19 to the result of the double.

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goldfiish [28.3K]

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